Brian Head's left arm is in a sling and his left knee is awaiting surgery to repair cartilage damage. It will be his fifth knee surgery since his senior year in high school.

Head listened to his battered body and has decided to end his college football career. He will be a student coach for the remainder of the season. Head, a fifth-year senior and Stanford's starter at center for most of the past three seasons, told coach Walt Harris and the other players that his career was over Tuesday night after a visit with his doctor, who said his injured shoulder is not responding to treatment.

Head sustained his shoulder injury in the UC Davis game, but his ailing knee had already been giving him trouble, leaving him wondering after the Navy game how he'd make it through the season.

"I've been fighting this off for a while," Head said. "I've battled through the knee surgeries, and this shoulder just wasn't getting any better. We were running out of options, and it seemed like the final prescription was rest and surgery, and that's where we are now."

Head has been replaced by Tim Mattran, who has started the past two games. Both Head and Harris are pleased with the way Mattran, a junior, has played.

"He's done an excellent job," Harris said. "Tim started here as a walk-on and he worked his way into the starting lineup. We rushed for 200-plus yards last week, so he obviously did some good things. That's a big step for us."

Harris said Head seemed relieved by his decision. Head said that did not make it easy.

"My locker is still in the locker room; I will still be hanging with the guys," Head said. "I'm going to keep them going and be on their butts, because now I really do live through them on the field."

Head's position as a student coach will allow him to travel with the team and provide instruction, counsel and motivation to young players such as Mikal Brewer and Chris Marinelli. He didn't picture himself as a coach.

"I'm not sure I could be cooped up in an office. I don't want to coach at the collegiate level. I think I'd like to be an offensive line coach at a local high school or something," Head said.

Egboh lost: Defensive end Pannel Egboh, the redshirt freshman who earned his first start last week at Washington State, will miss the remainder of the season with a broken left leg.

Egboh's injury, sustained late in the WSU game, is the second season-ending injury at that position for Stanford this season. Fifth-year senior Casey Carroll was sidelined by a knee injury during training camp.

"It's a huge loss," Harris said of Egboh. "He was getting better and better and it's a devastating blow to the team."

Injuries on the defensive line have prompted Harris to move Mike Macellari from the offensive line back to the defensive side. Macellari came to Stanford as a defensive lineman.